_:n7bb94fffb89f4ed78059fcf4a5783a1bxb1
<http://schema.org/isAccessibleForFree>
"true"^^<http://www.w3.org/2001/XMLSchema#boolean>
<https://intjem.biomedcentral.com/articles/10.1186/s12245-021-00376-3/figures/1>